JP5792056B2 - Mortar - Google Patents

Description

  The present invention relates to a coating mortar that is used as an undercoat conditioning material for a concrete structure.

  Various finishes are applied to the building structure depending on the construction site. The outer wall is tiled and finished paint is applied, and the roof is waterproofed such as waterproofing of the paint film and asphalt. In addition, indoors will be clothed, floored, and stoned on the entrance floor. The repair of the frame concrete during these constructions may take a water gradient when performing junker repairs, defect repairs, misplacement repairs, or rooftop waterproofing work.

  When repairing a concrete structure with mortar, a thick coating and a thin coating occur discontinuously. Generally, since repair is performed using two types of repair mortar for thin coating and repair mortar for thick coating, the repair work is complicated and time consuming. Therefore, a repair mortar that can be constructed from a construction thickness of 1 mm or less to about 10 mm in combination with pearlite pearlite, obsidian pearlite, and a water reducing agent has been devised (Patent Document 1). However, when pearlite and a water reducing agent are used in combination, they are easily affected by the environmental temperature during construction, and in the cold season, condensation is delayed and there is a risk of sagging when constructed on the outer wall.

  A repair mortar has been devised that uses lightweight aggregate, pozzolanic material, organic fiber, and polymer to improve adhesion to reinforced concrete, reduce drying shrinkage, and allows a single construction thickness of up to 60 mm (patent) Reference 2) In order to improve the thickening performance, this mortar has many lightweight aggregates and a large amount of water to be mixed, and the bending strength is lowered. Thickening performance is improved but thinning is difficult, so it is unsuitable for roofing waterproofing materials that require a water gradient.

  Moreover, when repairing a concrete structure, polymer cement mortar is generally used in order to impart adhesion, strength, and waterproofness to the frame concrete. In many cases, since a water retaining agent is used in combination with a polymer, the viscosity increases and the iron workability decreases. As a measure for improving the iron workability, a repair mortar having improved iron workability, adhesion and strength by using a silane compound and a polymer in combination has been devised (Patent Document 3).

JP 2004-175636 A Japanese Patent Laid-Open No. 11-199297 JP 2002-20153 A

  However, thin coating to thick coating is possible and does not satisfy the iron workability, adhesion, smoothness and bending rigidity, and a coating mortar that satisfies these requirements has been desired.

  Therefore, the present inventor has studied to solve the above problems, and as a result, in addition to fine aggregate, water retention agent, water repellent and fiber in cement, a polymer having a hydrophilic surface and a polymer having a hydrophobic surface. It was found that a coating mortar excellent in flexural rigidity, thick coating property, smoothness and trowel workability can be obtained by blending at a fixed ratio.

That is, the present invention relates to the following [1] to [5].
[1] (B) 80 to 103 parts by mass of fine aggregate, (C) 0.09 to 0.20 parts by mass of water retention agent, and (D) water repellent to 0.1 part of (A) 100 parts by mass of cement. 22-0.36
Parts by mass, (E) 0.14-0.43 parts by mass of fiber, and (F) (F1) surface hydrophilic polymer and (F2) surface hydrophobic polymer in a total solid content of 2.4-4.1. A coating mortar containing part by mass and having a content ratio (F2 / F1) of (F1) surface hydrophilic polymer and (F2) surface hydrophobic polymer of 0.18 to 0.43.
[2] (F1) The surface hydrophilic polymer is a surface hydrophilic re-emulsifying powder resin, (F2) The surface hydrophobic polymer is a surface hydrophobic re-emulsifying powder resin, a dispersion-type powder resin, and an emulsion-type powder. The coating mortar according to [1], which is a polymer selected from resins and powder resins obtained by treating these surfaces with a fatty acid salt or a silane compound.
[3] The coated mortar according to [1] or [2], wherein the fine aggregate is 104 to 122 parts by volume with respect to 100 parts by volume of cement, and the ratio of the lightweight aggregate in the fine aggregate is 60 to 70 vol%.
[4] (E) fibers consists tensile strength 1500 N / mm ² or more of the 1500 N / mm ² less than that, 100 parts by weight of cement relative to the tensile strength of 1500 N / mm ² or more fibers 0.04 The coating mortar according to any one of [1] to [3], containing 0.29 parts by mass.
[5] The coating mortar according to any one of [1] to [4], further containing one or more selected from (G) an expanding material, (H) a clay mineral, and (I) starches.

  The coating mortar of the present invention is excellent in bending rigidity, thick coating property, smoothness and trowel workability, and for applications such as tiles on the outer walls of concrete structures, finishing paint foundation adjustment, roof coating waterproofing foundation adjustment, etc. Very useful.

  The (A) cement used in the coating mortar of the present invention is not limited as long as it is hydraulic. Specifically, portland cement such as normal, early strength, super early strength, medium strength, low heat, etc., various mixed cements such as blast furnace cement and fly ash cement, and special cements such as white cement and eco cement Can do. You may use together cement other than having illustrated here, or 2 or more types of cement.

  The fine aggregate (B) used in the coating mortar of the present invention is not limited as long as it is used in ordinary mortar, but it is preferable to use ordinary aggregate and lightweight aggregate in combination. The ordinary aggregate may be any material as long as it can be used for mortar and concrete, and examples thereof include commercially available silica sand, cryolite, limestone sand, river sand, sea sand, mountain sand, and crushed sand. Further, as the lightweight aggregate, any of lightweight aggregates made of organic materials such as EVA calcium carbonate foam aggregate and styrene foam aggregate, and light aggregates made of natural or artificial inorganic materials can be used. The fine aggregate needs to be used in an amount of 80 to 103 parts by mass with respect to 100 parts by mass of cement, and is preferably used in an amount of 81 to 92 parts by mass, from the viewpoint of thick coatability and iron workability.

As the ordinary aggregate, commercially available silica sand, cold water stone, and limestone sand whose particle size is controlled are preferable for controlling the quality of the coating mortar of the present invention. For example, Asahi Silica Mining Co., Ltd. trade name “Asahi Silica Sand No. 5”, Tochu Co., Ltd. trade name “Kashima Silica Sand No. 6”, “Kashima Silica Sand No. 7”, Hitachi Kansui Stone Co., Ltd. trade name “Hitachi” "Samsui stone No. 1". The fine aggregate including the lightweight aggregate is preferably used in an amount of 104 to 122 parts by volume with respect to 100 parts by volume of cement. If the amount of the fine aggregate is small, the coatability deteriorates and the amount of shrinkage increases, which may cause cracks. On the other hand, if the amount is too large, the strength is lowered and the iron workability is lowered, which is not suitable. The proportion of the lightweight aggregate in the fine aggregate is preferably 60 to 70 vol%, more preferably 62 to 69 vol%. If there is little lightweight aggregate, thick coating property will fall, and if it coats thickly, sagging will occur. Furthermore, the viscosity increases and the workability of the iron also decreases. If there are too many lightweight aggregates, the strength will decrease and the amount of kneaded water will increase, the shrinkage after hardening will increase, and cracks may occur, which is not suitable.

The water retention agent (C) used in the coating mortar of the present invention may be any one that can be used in mortar or concrete, and examples thereof include water-soluble cellulose derivatives and polyvinyl alcohols. Examples of the water-soluble cellulose derivative include cellulose derivatives such as methyl cellulose, carboxymethyl cellulose, hydroxypropyl methyl cellulose, hydroxyethyl methyl cellulose, hydroxypropyl cellulose, and cellulose sulfate. For example, trade name “Metrozu SB” manufactured by Shin-Etsu Chemical Co., Ltd.
P30501 "can be used.

(C) By using a water retention agent, it is possible to improve the adhesion of the mortar to the concrete at the time of plastering, and it is possible to prevent the occurrence of dry cracks after curing and peeling / peeling. (C) 0.09-0.20 mass part is preferable with respect to 100 mass parts of cement, and, as for the usage-amount of a water retention agent, 0.09-0.15 mass part is more preferable.
By using in this range, adhesion, iron workability and the like are improved.

As the water repellent (D) used in the present invention, a silane water repellent is preferable. The silane water repellent is preferably a silane compound that is mixed with cement mortar and becomes reactive silanol under high alkaline conditions. For example, organic silane, polysilane and the like. As a specific example, there is a trade name “Seal 80” manufactured by Akzo Nobel Co., Ltd. The surface of reactive silanol is modified to be hydrophobic by crosslinking between silanol groups or reaction with an inorganic compound. Therefore, the silane water repellent has good kneading properties, and the highly durable finish of the present invention exhibits excellent water repellency after curing.

  (D) The water repellent is preferably used in an amount of 0.22 to 0.36 parts by mass, more preferably 0.22 to 0.30 parts by mass with respect to 100 parts by mass of cement. When there are too few water repellents, appropriate water repellency cannot be obtained and there is no mixed effect. On the other hand, if the amount is too large, the improvement of the water repellent effect is small and uneconomical.

  The (E) fiber used in the present invention is preferably an alkali resistant fiber. The alkali resistant fiber preferably has a fiber length of 10 mm or more so as not to reduce the thick coatability and bending strength as the coating mortar. Commercially available fibers include single fibers and convergent types, but both can be used. Furthermore, a fiber length of 10 to 25 mm is preferable. If the fiber length is too short, there is an effect of stopping drooping, but an effect of improving the bending strength cannot be obtained. Organic fibers and glass fibers that are miscible with mortar can be used as long as they have alkali resistance, and they can be used in combination. As the organic fiber, polyester, acrylic, nylon, polypropylene or the like can be used, and glass fiber having alkali resistance can be used as the glass fiber.

  (E) The amount of the fiber used is preferably 0.14 to 0.43 parts by mass, more preferably 0.15 to 100 parts by mass with respect to 100 parts by mass of cement, from the viewpoint of improving thick coatability, bending strength, and iron workability. 0.39 mass part is good.

In order to simultaneously improve thick coatability, bending strength, and iron workability as a thick coat mortar, it is preferable to use a fiber having a tensile strength of 1500 N / mm ² or more and a fiber of less than 1500 N / mm ² . It is preferable to use 0.04 to 0.29 parts by mass of fibers having a tensile strength of 1500 N / mm ² or more with respect to 100 parts by mass of cement, and more preferably 0.05 to 0.29 parts by mass.

In the present invention, it is necessary to use (F) (F1) surface hydrophilic polymer and (F2) surface hydrophobic polymer in view of improving the workability of the iron. Usually, a re-emulsified powder resin blended in cement has a hydrophobic polymer surface, and when used in combination with a water retention agent such as a cellulose derivative, the viscosity becomes too high and the iron workability is lowered. In the present invention, in addition to the polymer (F2) whose surface is hydrophobic, in combination with the polymer (F1) whose surface is hydrophilic, an increase in viscosity during construction can be suppressed, and the iron workability is improved.
(F1) Surface hydrophilic polymer includes surface hydrophilic re-emulsifying powder resin, and the resin surface is treated with, for example, polyvinyl alcohol, polyacrylic acid, polyvinyl pyrrolidone, polyacrylamide, polyethyleneimine, polyethylene oxide, etc. An emulsified powder resin may be mentioned. Of these, re-emulsified powder resin treated with polyvinyl alcohol is more preferred. Examples of the powder resin main body include resins mainly composed of ethylene vinyl acetate, vinyl acetate / versatechnic acid vinyl ester, vinyl acetate / vinyl versatate / acrylic acid ester, and polyacrylic acid ester.

  (F2) Surface hydrophobic polymer includes surface hydrophobic re-emulsifying powder resin, dispersion-type powder resin, emulsion-type powder resin, and powder resin whose surface is treated with a fatty acid salt, a silane compound, or the like. . Examples of these powder resin bodies include resins mainly composed of ethylene vinyl acetate, vinyl acetate / versatechnic acid vinyl ester, vinyl acetate / versatechnic acid vinyl / acrylic acid ester, polyacrylic acid ester, and the like.

  These (F) polymers are preferably used in an amount of 2.4 to 4.1 parts by mass, more preferably 2.7 to 3.5 parts by mass based on 100 parts by mass of cement. is there. If the amount is less than 2.4 parts by mass, suitable adhesion strength cannot be obtained and the amount of water absorption increases. When the amount exceeds 4.1 parts by mass, the workability of the iron is lowered and the risk of ignition of the thick mortar of the present invention increases when a fire occurs in a nearby building structure. Furthermore, the content ratio (F2 / F1) of (F1) surface hydrophilic polymer and (F2) surface hydrophobic polymer is preferably 0.18 to 0.43, more preferably 0.37 to 0.42. If it is less than 0.18, the improvement effect of iron workability cannot be obtained. When it exceeds 0.43, the viscosity is lowered and the thick coatability is lowered.

  In addition to the said component, the coating mortar of this invention can mix | blend 1 type (s) or 2 or more types chosen from (G) expansion | swelling material, (H) clay mineral, and (I) starches.

The (G) expandable material that can be used in the coating mortar of the present invention is not particularly limited as long as it can be used for mortar and concrete. Mention may be made of fore luminescence as an active ingredient. By blending and using the expansion material, drying shrinkage is mainly suppressed, the shape and dimension stability of the construction site can be achieved, and the occurrence of shrinkage cracks can be prevented. For example, trade name “Pacific Expan (for structure)” manufactured by Taiheiyo Material Co., Ltd., trade name “Pacific Gypcal”, and the like can be given.
(G) The amount of the expansion material used is preferably 4.5 to 5.7 parts by mass, more preferably 4.7 to 5.7 parts by mass with respect to 100 parts by mass of cement in terms of shrinkage reduction effect, crack prevention, and the like. Part.

The (H) clay mineral that can be used in the coating mortar of the present invention is preferably sepiolite or bentonite that has an effect of improving the iron workability. Sepiolite is a fibrous hydrous magnesium silicate. The clay minerals have a channel structure stacked on top of each other and are porous and fibrous in shape with a large specific surface area. For example, Sepiolite can use the trade name “IGS” manufactured by Sakai Kogyo Co., Ltd.
The amount of the clay mineral used is preferably 0.2 to 0.9 parts by mass, more preferably 0.2 to 0.6 parts by mass with respect to 100 parts by mass of cement, from the viewpoint of improving the workability of the iron and preventing cracks. is there.

  (I) As starches, starch ether, corn starch, and potato starch can be used. Examples of the starch ether include SKW East Asia Co., Ltd. trade names “Tyrobis SE-7”, “STARVIS SE25F”, and the like. Since the starches are intended to improve the iron workability, the amount of use is preferably 0.01 to 0.03 parts by mass, more preferably 0.015 to 0.025 parts by mass with respect to 100 parts by mass of cement. It is.

  In the coating mortar of the present invention, various admixtures and additives usually used for cement compositions can be used. For example, mineral oil-based, polyether-based, and silicone-based antifoaming agents can be used. Further, various slag powders; pozzolanic substances such as fly ash and silica fume, curing accelerators, curing retarders and the like can be used.

  The coating mortar of the present invention is mixed with the above components by adding water and used for normal coating work, for example, trowel coating, tiles on the outer wall of concrete structures, finishing paint foundation adjustment, roof coating waterproofing foundation adjustment, etc. be able to.

  EXAMPLES Next, an Example is given and this invention is demonstrated still in detail.

Examples 1-15 and Comparative Examples 1-14
Using the materials shown in Table 1, coating mortars having the formulations shown in Tables 2 and 3 were produced.

  Using the coating mortar of Table 2 and Table 3, bending strength (material age 28 days), compressive strength (material age 28 days), adhesion strength (material age 2 days), length change rate and water absorption were measured. The measurement methods are shown in Table 4, and the evaluation methods are shown in Tables 5 to 7. Test results are shown in Tables 8-9.

  Next, the iron workability was evaluated using the coating mortars shown in Tables and Table 3.

(Test method)
400x45 in 10mm thickness on 450x900x60mm concrete slab in 20 ° C test room
Each sample was applied with a gold iron within a range of 0 mm to evaluate the iron workability.
(1) Solder cut The sample did not adhere to the gold trowel and was applied smoothly within 2 times.
The sample does not adhere to the gold trowel, but it took more than 3 times to apply it smoothly.
A sample adhered to a gold trowel ×
(2) Iron elongation The sample can be easily spread with a gold trowel and smoothed.
The sample can be easily spread with a gold trowel, but it takes 3 or more times to apply it smoothly.
The sample cannot be easily spread with a gold trowel ×
(3) Presence / absence of sag No sag

  The results are shown in Table 10 and Table 11.

  As is apparent from Tables 1 to 11, the coating mortar of the present invention had good bending strength, compressive strength, adhesion, and good workability.

Claims (5)

  (A) 80 to 103 parts by mass of fine aggregate with respect to 100 parts by mass of cement, (C) 0.09 to 0.20 parts by mass of water retention agent, and (D) 0.22 to 0 of water repellent. .36 parts by mass, (E) 0.14 to 0.43 parts by mass of fiber, and (F) (F1) surface hydrophilic polymer and (F2) surface hydrophobic polymer in a total solid content of 2.4 to 4 A coating mortar containing 1 part by mass and having a content ratio (F2 / F1) of (F1) surface hydrophilic polymer and (F2) surface hydrophobic polymer of 0.18 to 0.43.   (F1) the surface hydrophilic polymer is a surface hydrophilic re-emulsifying powder resin, and (F2) the surface hydrophobic polymer is a surface hydrophobic re-emulsifying powder resin, a dispersion-type powder resin, an emulsion-type powder resin, and The coating mortar according to claim 1, which is a polymer selected from powder resins obtained by treating these surfaces with a fatty acid salt or a silane compound.   The coated mortar according to claim 1 or 2, wherein the fine aggregate is 104 to 122 parts by volume with respect to 100 parts by volume of cement, and the ratio of the lightweight aggregate in the fine aggregate is 60 to 70 vol%. (E) fibers, the tensile strength 1500 N / mm consists of ^two or more of the 1500 N / mm ² less than that, 100 parts by weight of cement relative to the tensile strength of 1500 N / mm ² or more fibers 0.04 to 0.29 The coating mortar according to any one of claims 1 to 3, which contains part by mass.   Furthermore, the coating mortar in any one of Claims 1-4 containing 1 type, or 2 or more types chosen from (G) expansion | swelling material, (H) clay mineral, and (I) starches.